• Title/Summary/Keyword: $BF_3$

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Volume Expansion of Ionic Liquids in the Presence of Supercritical Carbon Dioxide (초임계이산화탄소의 존재 하에서 이온성액체의 부피팽창)

  • Lim, Bang-Hyun;Shim, Jae-Jin
    • Clean Technology
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    • v.14 no.4
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    • pp.248-255
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    • 2008
  • The volume expansion of three ionic liquids (ILs) in the presence of supercritical carbon dioxide has been measured at pressures up to 32 MPa and at temperatures from 313.15 to 333.15 K in a high-pressure view cell. The imidazolium-derivative ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][$PF_6$]), 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][$BF_4$]), and 1-octyl-3-methylimidazolium tetrafluoroborate ([omim][$BF_4$]) were employed in this research. The effects of pressure, temperature, nature of anion and cation as well as the water content on the volume expansion of ILs by absorbing $CO_2$ were investigated experimentally. The volume expansion was higher for the ILs with longer cationic alkyl group and for the ILs with lower anion polarity. The lower the water content, the lower the temperature, or the higher the pressure, the higher was the expansion of IL phase.

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Esterification of Methacrylic acid with Ethylene glycol over Heteropolyacid supported on ZSM-5 (ZSM-5 위에 지지된 Heteropolyacid 하에서 Methacrylic acid와 Ethylene glycol의 에스테르화 반응)

  • Prabhakarn, A.;Fereiro, J.A.;Subrahmanyam, Ch.
    • Journal of the Korean Chemical Society
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    • v.55 no.1
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    • pp.14-18
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    • 2011
  • Esterification of methacrylic acid with ethylene glycol was carried out over Heteropolyacids [HPA: $H_4SiW_{12}O_{40}$ (STA) and $H_3PW_{12}O_{40}$ (PTA)] supported on ZSM-5. For comparison, the same reaction was carried out over unsupported HPA, $H_2SO_4$, $BF_3$ and PTSA. Among the catalysts studied, HPA showed better activity compared to $H_2SO_4$, $BF_3$ and PTSA. Catalytic activity was compared with HPA supported ZSM-5 catalysts. Typical results indicated that 30 wt% PTA supported on ZSM-5 showed nearly the same activity as that of bulk PTA. It was found that the reaction follows first order kinetics with respect to methacrylic acid. The reaction products were identified by $^1H$-NMR and FT-IR.

Effect of Deboning Time on Quality Characteristics of Pressed Pork Ham (돈육 뒷다리 부위의 발골시간이 프레스햄의 품질 특성에 미치는 영향)

  • Yang, H.S.;Joo, S.T.;Park, Gu-Boo
    • Journal of Animal Science and Technology
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    • v.49 no.3
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    • pp.387-394
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    • 2007
  • To investigate the effects of deboning time and muscle type of ham on quality characteristics of cooked press ham, a total of twelve pigs(barrow, 100±5kg) were slaughtered and split in half. The left side ham of carcasses was deboned immediately after slaughter whereas the right side ham was deboned after chilling for 24 hours at 4℃. Each of two muscles(SM; Semimembranosus, BF; Biceps femoris) was used to make a press ham. The pH of hot-boning muscles was significantly(p<0.05) higher than that of cold- boning muscles, and the pH of SM samples was significantly(p<0.05) higher than BF samples. Hot-boning muscles showed significantly(p<0.05) longer sarcomere length compared with cold-boning muscles. There was no significant difference in myoglobin(Mb) percentage between SM and BF muscles, but SM samples of hot-boning showed significantly(p<0.05) lower L* value compared to hot-boning BF samples. The lightness(L*) of hot-boning muscles was significantly(p<0.05) lower than that of cold-boning muscles. These results suggested that the dark color of hot-boning samples might be due to not only the high muscle pH but also the long sarcomere length without difference in Mb percentage. Hardness and gumminess of hot-boning press ham were significantly(p<0.05) lower than those of cold-boning samples. These results implied that color and pH of press ham did not affected by deboning time or muscle type of ham. However data suggested that texture and panel test of press ham might be improved by using hot-boned muscle due to long sarcomere length of raw meat.

The Use of Fermented Soybean Meals during Early Phase Affects Subsequent Growth and Physiological Response in Broiler Chicks

  • Kim, S.K.;Kim, T.H.;Lee, S.K.;Chang, K.H.;Cho, S.J.;Lee, K.W.;An, B.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.9
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    • pp.1287-1293
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    • 2016
  • The objectives of this experiment was to evaluate the subsequent growth and organ weights, blood profiles and cecal microbiota of broiler chicks fed pre-starter diets containing fermented soybean meal products during early phase. A total of nine hundred 1-d-old chicks were randomly assigned into six groups with six replicates of 25 chicks each. The chicks were fed control pre-starter diet with dehulled soybean meal (SBM) or one of five experimental diets containing fermented SBM products (Bacillus fermented SBM [BF-SBM], yeast by product and Bacillus fermented SBM [YBF-SBM]; Lactobacillus fermented SBM 1 [LF-SBM 1]; Lactobacillus fermented SBM 2 [LF-SBM 2]) or soy protein concentrate (SPC) for 7 d after hatching, followed by 4 wk feeding of commercial diets without fermented SBMs or SPC. The fermented SBMs and SPC were substituted at the expense of dehulled SBM at 3% level on fresh weight basis. The body weight (BW) during the starter period was not affected by dietary treatments, but BW at 14 d onwards was significantly higher (p<0.05) in chicks that had been fed BF-SBM and YBF-SBM during the early phase compared with the control group. The feed intake during grower and finisher phases was not affected (p>0.05) by dietary treatments. During total rearing period, the daily weight gains in six groups were 52.0 (control), 57.7 (BF-SBM), 58.5 (YBF-SBM), 52.0 (LF-SBM 1), 56.7 (LF-SBM 2), and 53.3 g/d (SPC), respectively. The daily weight gain in chicks fed diet containing BF-SBM, YBF-SBM, and LF-SBM 2 were significantly higher values (p<0.001) than that of the control group. Chicks fed BF-SBM, YBF-SBM, and LF-SBM 2 had significantly lower (p<0.01) feed conversion ratio compared with the control group. There were no significant differences in the relative weight of various organs and blood profiles among groups. Cecal microbiota was altered by dietary treatments. At 35 d, chicks fed on the pre-starter diets containing BF-SBM and YBF-SBM had significantly increased (p<0.001) lactic acid bacteria, but lowered Coli-form bacteria in cecal contents compared with those fed the control diet. The number of Bacillus spp. was higher (p<0.001) in all groups except for LF-SBM 1 compared with control diet-fed chicks. At 7 d, jejunal villi were significantly lengthened (p<0.001) in chicks fed the fermented SBMs vs control diet. Collectively, the results indicate that feeding of fermented SBMs during early phase are beneficial to the subsequent growth performance in broiler chicks. BF-SBM and YBF-SBM showed superior overall growth performance as compared with unfermented SBM and SPC.

Amino Acid Concentrations in the Blastocoelic Fluid of In Vitro-Produced Bovine Blastocysts (체외생산된 소 배반포강 내의 아미노산 농도)

  • Jung, Y.G.;Wei, H.;Yoon, J.T.;Fukui, Y.
    • Journal of Embryo Transfer
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    • v.13 no.3
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    • pp.251-259
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    • 1998
  • Concentrations of free amino acids in the BF of IVP bovine BL and HBL were examined in this study. The embryos derived from IVF oocytes were cultured in a SOFM containing BSA, EAA and NEAA. BF was aspirated from BL (180 h of age after insemination) and HBL (216 h of age after insemination), and introduced into drops of SOFM (30$\mu$l/drop) containing PVA through micromanipulation. The medium containing BF was then subjected to measurement of 20 amino acids by an automatic amino acid analyzer. The concentrations of isoleucine, leucine and methionine were higher (p〈0.05) in the BF from HBL than from BL, and no difference was found in aspartate or glutamate concentrations between BL and HBL, while threonine, alanine (p〈0.01) and the rest of the amino acids (p〈0.001) were significantly higher in the BF from HBL than from BL. Cystine was not found in either BL or HBL. A high concentration of glutamine was found in the BF from both BL and HBL, although it was not added to the culture medium. These results indicate that bovine BF contains several EAA (methionine in BL and isoleucine, leucine and methionine in HBL) and NEAA (alanine, glutamate, glycine, proline, serine and aspartate in BL, and glutamate and aspartate in HBL), and there is significant differences in the amino acid concentration in the BF between BL and HBL derived by WP.

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Accuracy of Body Mass Index-defined Obesity Status in US Firefighters

  • Jitnarin, Nattinee;Poston, Walker S.C.;Haddock, Christopher K.;Jahnke, Sara A.;Day, Rena S.
    • Safety and Health at Work
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    • v.5 no.3
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    • pp.161-164
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    • 2014
  • Obesity is a significant problem affecting United States (US) firefighters. While body mass index (BMI) is widely used to diagnose obesity, its use for this occupational group has raised concerns about validity. We examined rates and types of misclassification of BMI-based obesity status compared to body fat percentage (BF%) and waist circumference (WC). Male career firefighters (N = 994) from 20 US departments completed all three body composition assessments. Mean BMI, BF%, and WC were $29kg/m^2$, 23%, and 97 cm, respectively. Approximately 33% and 15% of BF%- and WC-defined obese participants were misclassified as non-obese (false negatives) using BMI, while 8% and 9% of non-obese participants defined by BF% and WC standards were identified as obese (false positives) using BMI. When stratified by race/ethnicity, Pacific Islanders showed high rates of false positive misclassification. Precision in obesity classification would be improved by using WC along with BMI to determine firefighters' weight status.

Sum Rate Approximation of Zero-Forcing Beamforming with Semi-Orthogonal User Selection

  • Yang, Jang-Hoon;Jang, Seung-Hun;Kim, Dong-Ku
    • Journal of Communications and Networks
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    • v.12 no.3
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    • pp.222-230
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    • 2010
  • In this paper, we present a closed-form approximation of the average sum rate of zero-forcing (ZF) beamforming (BF) with semi-orthogonal user selection (SUS). We first derive the survival probability associated with the SUS that absolute square of the channel correlation between two users is less than the orthogonalization level threshold (OLT).With this result, each distribution for the number of surviving users at each iteration of the SUS and the number of streams for transmission is calculated. Secondly, the received signal power of ZF-BF is represented as a function of the elements of the upper triangular matrix from QR decomposition of the channel matrix. Thirdly, we approximate the received signal power of ZF-BF with the SUS as the maximum of scaled chisquare random variables where the scaling factor is approximated as a function of both OLT and the number of users in the system. Putting all the above derivations and order statistics together, the approximated ergodic sum rate of ZF-BF with the SUS is shown in a closed form. The simulation results verify that the approximation tightly matches with the sample average for any OLT and even for a small number of users.

The Effects of Co-60 ${\gamma}-irradiation$ causing Enzyme Histochemical Changes of Bursa Fabricius, Thymus and Spleen in Chicken (Co-60 ${\gamma}$선(線) 조사(照射)가 병아리의 F낭, 흉선 및 비장의 효소(酵素) 조직화학적(組織化學的) 변화(變化)에 미치는 영향(影響))

  • Lee, Dong-Myoung
    • Journal of radiological science and technology
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    • v.13 no.1
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    • pp.29-35
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    • 1990
  • In a attempt to find out the effects of the irradiation on the lymphatic organs of birds, a total of 40 chickens(4 week old) were selected at random and alloted to control and experimental groups. The experiments were irradiated Co-60 ${\gamma}-ray/400$ rads, and then the enzyme histochemical activity of Bursa Fabricious(BF), thymus and spleen and hematological changes were compared with those of controls for 30 days(24 hrs., 5, 10, 20 and 30 days). The results obtained were summarized as follows: 1. The activity of acid phosphatase(ACP) of the reticuloendothelial cells of BF, thymus and spleen and the epithelia of BF of the experiments were increased significantly from the early experimental terms and then returned to the same level of controls through the late experimental terms. 2. The activity of nonspecific esterase(NSE) of the constituent cells with exception of the lymphocytes in BF, thymus and spleen of experiments were increased significantly from the early experimental terms and then returned to the same level of control through the late experimental terms. 3. The lymphocyte percentage, total erythrocytes and homoglobin of the experiments were severely decreased from early experimental terms and then increased to the normal levels of them incontrols.

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Dyssynergic Defecation in Chronically Constipated Children in Korea

  • Sun Hwan Bae
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.26 no.2
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    • pp.127-133
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    • 2023
  • Purpose: Dyssynergic defecation (DSD) is one of the important causes of chronic constipation in children. We aimed to analyze the clinical features, diagnostic test results, and treatments for DSD in children. Methods: Children diagnosed with DSD using fluoroscopic defecography were enrolled in this study. Clinical data, including the results of colon transit time (CTT) test and biofeedback (BF) therapy, were collected from medical records retrospectively. Results: Nineteen children were enrolled. The median age was 9 years (6-18 years), the median frequency of bowel movement was 1/7 days (1-10 days), the median duration of constipation was 7.0 years (2-18 years), the median age of onset of constipation was 2.5 years (1-11 years). In the CTT test, outlet obstruction type was noted in 10/18 (55.6%), slow transit type in 5/18 (27.8%), and normal transit in 1/18 (5.6%). The median CTT was 52 hours (40-142 hours). Initial medical therapy was performed with the polyethylene glycol 4000, and the response was good in 9/19 (47.4%), fair in 9/19 (47.4%), and poor in 1/19 (5.0%). BF was performed in 8/19, with good results in 6/8 (75.0%) children and failure in 2/8 (25.0%) children. After long-term medical therapy (11/19), 3/5 showed good response with medication alone, 6/8 showed good response with BF and medication combined. Conclusion: DSD should be considered as a cause of chronic constipation in children, especially in those with abnormal CTT test results. BF combined with medical therapy is effective even with age-limited cooperation.